1 files changed, 130 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/btf_dump.c b/tools/testing/selftests/bpf/prog_tests/btf_dump.c
new file mode 100644
index 000000000000..7390d3061065
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/btf_dump.c
@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <test_progs.h>
+#include <bpf/btf.h>
+
+static int duration = 0;
+
+void btf_dump_printf(void *ctx, const char *fmt, va_list args)
+{
+	vfprintf(ctx, fmt, args);
+}
+
+static struct btf_dump_test_case {
+	const char *name;
+	const char *file;
+	struct btf_dump_opts opts;
+} btf_dump_test_cases[] = {
+	{"btf_dump: syntax", "btf_dump_test_case_syntax", {}},
+	{"btf_dump: ordering", "btf_dump_test_case_ordering", {}},
+	{"btf_dump: padding", "btf_dump_test_case_padding", {}},
+	{"btf_dump: packing", "btf_dump_test_case_packing", {}},
+	{"btf_dump: bitfields", "btf_dump_test_case_bitfields", {}},
+	{"btf_dump: multidim", "btf_dump_test_case_multidim", {}},
+	{"btf_dump: namespacing", "btf_dump_test_case_namespacing", {}},
+};
+
+static int btf_dump_all_types(const struct btf *btf,
+			      const struct btf_dump_opts *opts)
+{
+	size_t type_cnt = btf__get_nr_types(btf);
+	struct btf_dump *d;
+	int err = 0, id;
+
+	d = btf_dump__new(btf, NULL, opts, btf_dump_printf);
+	if (IS_ERR(d))
+		return PTR_ERR(d);
+
+	for (id = 1; id <= type_cnt; id++) {
+		err = btf_dump__dump_type(d, id);
+		if (err)
+			goto done;
+	}
+
+done:
+	btf_dump__free(d);
+	return err;
+}
+
+static int test_btf_dump_case(int n, struct btf_dump_test_case *t)
+{
+	char test_file[256], out_file[256], diff_cmd[1024];
+	struct btf *btf = NULL;
+	int err = 0, fd = -1;
+	FILE *f = NULL;
+
+	snprintf(test_file, sizeof(test_file), "%s.o", t->file);
+
+	btf = btf__parse_elf(test_file, NULL);
+	if (CHECK(IS_ERR(btf), "btf_parse_elf",
+	    "failed to load test BTF: %ld\n", PTR_ERR(btf))) {
+		err = -PTR_ERR(btf);
+		btf = NULL;
+		goto done;
+	}
+
+	snprintf(out_file, sizeof(out_file), "/tmp/%s.output.XXXXXX", t->file);
+	fd = mkstemp(out_file);
+	if (CHECK(fd < 0, "create_tmp", "failed to create file: %d\n", fd)) {
+		err = fd;
+		goto done;
+	}
+	f = fdopen(fd, "w");
+	if (CHECK(f == NULL, "open_tmp",  "failed to open file: %s(%d)\n",
+		  strerror(errno), errno)) {
+		close(fd);
+		goto done;
+	}
+
+	t->opts.ctx = f;
+	err = btf_dump_all_types(btf, &t->opts);
+	fclose(f);
+	close(fd);
+	if (CHECK(err, "btf_dump", "failure during C dumping: %d\n", err)) {
+		goto done;
+	}
+
+	snprintf(test_file, sizeof(test_file), "progs/%s.c", t->file);
+	if (access(test_file, R_OK) == -1)
+		/*
+		 * When the test is run with O=, kselftest copies TEST_FILES
+		 * without preserving the directory structure.
+		 */
+		snprintf(test_file, sizeof(test_file), "%s.c", t->file);
+	/*
+	 * Diff test output and expected test output, contained between
+	 * START-EXPECTED-OUTPUT and END-EXPECTED-OUTPUT lines in test case.
+	 * For expected output lines, everything before '*' is stripped out.
+	 * Also lines containing comment start and comment end markers are
+	 * ignored. 
+	 */
+	snprintf(diff_cmd, sizeof(diff_cmd),
+		 "awk '/START-EXPECTED-OUTPUT/{out=1;next} "
+		 "/END-EXPECTED-OUTPUT/{out=0} "
+		 "/\\/\\*|\\*\\//{next} " /* ignore comment start/end lines */
+		 "out {sub(/^[ \\t]*\\*/, \"\"); print}' '%s' | diff -u - '%s'",
+		 test_file, out_file);
+	err = system(diff_cmd);
+	if (CHECK(err, "diff",
+		  "differing test output, output=%s, err=%d, diff cmd:\n%s\n",
+		  out_file, err, diff_cmd))
+		goto done;
+
+	remove(out_file);
+
+done:
+	btf__free(btf);
+	return err;
+}
+
+void test_btf_dump() {
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(btf_dump_test_cases); i++) {
+		struct btf_dump_test_case *t = &btf_dump_test_cases[i];
+
+		if (!test__start_subtest(t->name))
+			continue;
+
+		 test_btf_dump_case(i, &btf_dump_test_cases[i]);
+	}
+}